usb: cdnsp: fix error handling in cdnsp_mem_init()

This function uses "One Function Cleans up Everything" style and that's
basically impossible to do correctly. It's cleaner to write it with
"clean up the most recent allocation".

Patch fixes two isues:
1. If pdev->dcbaa = dma_alloc_coherent() fails then that leads to a NULL
   dereference inside the cdnsp_free_priv_device() function.
2. if cdnsp_alloc_priv_device() fails that leads to a double free because
   we free pdev->out_ctx.bytes in several places.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Tested-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>